<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>118 - Disclosure - INVESTMENT IN LIFE SETTLEMENTS TRUST</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><CurrencyCode /><FootnoteIndexer /><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><MCU><KeyName /><CurrencySymbol /><contextRef><ContextID>P03_01_2013To05_31_2013</ContextID><EntitySchema>http://www.sec.gov/CIK</EntitySchema><EntityValue>0000049534</EntityValue><PeriodDisplayName /><PeriodType>duration</PeriodType><PeriodStartDate>2013-03-01T00:00:00</PeriodStartDate><PeriodEndDate>2013-05-31T00:00:00</PeriodEndDate><Segments /><Scenarios /></contextRef><UPS /><CurrencyCode /><OriginalCurrencyCode /></MCU><CurrencySymbol /><Labels><Label Key="CalendarSupplement" Id="0" Label="3 Months Ended" /><Label Key="Calendar" Id="1" Label="May 31, 2013" /></Labels></Column></Columns><Rows><Row FlagID="0"><Id>1</Id><IsAbstractGroupTitle>true</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>1</Level><ElementName>us-gaap_InvestmentsAllOtherInvestmentsAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Investments, All Other Investments [Abstract]</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>2</Level><ElementName>us-gaap_LifeSettlementContractsDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>terseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="P03_01_2013To05_31_2013" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText> &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif "&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;MARGIN: 0pt 0px; FONT: bold 10pt Times New Roman, Times, Serif"&gt; (9) INVESTMENT IN LIFE SETTLEMENTS TRUST&lt;/div&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif" align="justify"&gt;&amp;#160;&lt;/div&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif" align="justify"&gt;The amount shown on the balance sheet termed &amp;#8220;Investment in Life Settlements Trust&amp;#8221; is an investment in an unaffiliated corporation, Life Assets Trust, S.A., (the &amp;#8220;&lt;em&gt;Trust&lt;/em&gt;&amp;#8221;) created for the acquisition of life settlements. As of May&amp;#160;31, 2013, and February&amp;#160;28, 2013, we owned 19.9% of the trust, carried at $6.6 million and $6.7 million, respectively, and accounted for on the equity method of accounting. At May 31, 2013, the Trust owned a portfolio of 231 life insurance settlements with a face value of $613.3 million, of which LPI supplied settlements with a face value of approximately $278&amp;#160;million. We anticipate the policies will mature over the next few years, although we cannot determine the exact time of the policy maturities and the distribution of the underlying assets. We have considered any potential impairment to the investment and believe no impairment to the investment value is warranted.&lt;/div&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif" align="justify"&gt;&amp;#160;&lt;/div&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif" align="justify"&gt;On May 24, 2013, we entered into Assignments of Right to Receive Future Payments (the &amp;#8220;&lt;em&gt;Assignments&lt;/em&gt;&amp;#8221;) with four unaffiliated, accredited investors (the &amp;#8220;&lt;em&gt;Assignees&lt;/em&gt;&amp;#8221;), in which we assigned to the Assignees the right to receive amounts otherwise payable to us from our investment in Life Assets Trust, S.A., &lt;font style="COLOR: black"&gt;a Luxembourg joint stock company&lt;/font&gt; (the &amp;#8220;&lt;em&gt;Trust&lt;/em&gt;&amp;#8221;).&amp;#160; In exchange for the right, the Assignees paid us $5,650,000.&amp;#160; We retain a reversionary interest in the assigned economic rights in the Trust, which is triggered when the Assignees receive cumulative payments of $9,411,667 assuming the payments have provided an annually compounded rate of return of 12% or more on amounts invested.&amp;#160; If the Assignees have not received the required return, they will continue to receive payments until they receive the 12% return on their invested amount.&amp;#160; The Assignments provide that payments from the Trust are deposited with an escrow agent, which remits the payments to the Assignees. Because of the Assignments, we do not anticipate distributions from the Trust for several years.&lt;/div&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif" align="justify"&gt;&amp;#160;&amp;#160;&lt;/div&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif" align="justify"&gt;&lt;font style="COLOR: black"&gt;&lt;/font&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-ALIGN: justify; TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt; &lt;font style="COLOR: black"&gt;&lt;font style="COLOR: black"&gt;Before the Assignments, the Trust distributed $227,508&lt;/font&gt; and $48,289&lt;/font&gt; in the First Quarter of this year and last year respectively, which was before the Assignments discussed above.&lt;/div&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-ALIGN: justify; TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt; &amp;#160;&lt;/div&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-ALIGN: justify; TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt; The Assignees are each private investors, who have purchased life settlements from us previously. Apart from these purchases, they have no affiliation with us or our directors or officers.&lt;/div&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-ALIGN: justify; TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt; &amp;#160;&lt;/div&gt; &lt;div style="clear:both;FONT-FAMILY: 'Times New Roman','serif'; FONT-SIZE: 10pt;TEXT-ALIGN: justify; TEXT-INDENT: 0.5in; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt; A referral fee of $395,500 was paid to an unaffiliated individual in connection with the assignment.&lt;/div&gt; &lt;/div&gt; &lt;/div&gt; </NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for life settlement contracts including the accounting policy for life settlement contracts and the classification of cash receipts and cash disbursements in the statement of cash flows and, as applicable, for (1) life settlement contracts accounted for under the investment method based on the remaining life expectancy for each of the first five succeeding years from the date of the statement of financial position and thereafter, as well as in the aggregate: (a) the number of life settlement contracts, (b) the carrying value of the life settlement contracts, and (c) the face value (death benefits) of the life insurance policies underlying the contracts, (d) the life insurance premiums anticipated to be paid for each of the five succeeding fiscal years to keep the life settlement contracts in force as of the date of the most recent statement of financial position presented, (e) the nature of the information that causes the Entity to change its expectations on the timing of the realization of proceeds from the investments in life settlement contracts and the related effect on the timing of the realization of proceeds from the life settlement contracts and for (2) life settlement contracts accounted for under the fair value method, disclosure would include, based on remaining life expectancy for each of the first five succeeding years from the date of the statement of financial position and thereafter, as well as in the aggregate: (a) the number of life settlement contracts, (b) the carrying value of the life settlement contracts, (c) the face value (death benefits) of the life insurance policies underlying the contracts, (d) the reasons for changes in the Entity's expectation of the timing of the realization of the investments in life settlement contracts, and (e) (i) the gains or losses recognized during the period on investments sold during the period and (ii) the unrealized gains or losses recognized during the period on investments that are still held at the date of the statement of financial position.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

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