President can Invoke 31 USC 3102 -- the debt law itself!

THE SECRETARY OF THE TREASURY'S AUTHORITY WITH
RESPECT TO THE CIVIL SERVICE RETIREMENT AND
DISABILITY FUND
Nov. 10 1995

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You have requested advice from this Office on the Secretary of the Treasury's ("Secretary") authority with respect to the investment assets of the Civil Service Retirement and Disability Fund ("CSRDF" or "Fund") during a debt limit crisis. Specifically, you have asked this Office:

(1) whether the statute governing the Fund allows the Secretary to suspend the investment of Fund contributions in Treasury-issued, United States debt obligations that are subject to 31 U.S.C. § 3101(b) (the "debt limit") (such debt obligations herein referred to as "obligations of the United States") during a debt limit crisis;

(2) whether the Secretary has the authority to disinvest or redeem Fund investment assets during a debt limit crisis; and

(3) if the Secretary has the authority to disinvest or redeem, the conditions under which such authority may be exercised.

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You have informed us that Treasury is considering altering this process during the impending debt limit crisis. You have suggested that the Secretary might be prohibited by the debt limit from investing additional CSRDF contributions.

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Congress in 1986 established rules under which the Secretary could, during a debt limit crisis, suspend the investment of Fund contributions and take other related ameliorative actions involving the Fund.

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Obligations of the United States issued to the CSRDF are subject to the debt limit. See 5 U.S.C. § 8348(d).(4) Concerned that a failure to increase the debt limit might negatively affect the Fund's financial condition(5) and apparently aware of the overriding public interest in ensuring that a debt limit crisis not trigger default on obligations of the United States,(6) Congress in 1986 established rules under which the Secretary could, during a debt limit crisis, suspend the investment of Fund contributions and take other related ameliorative actions involving the Fund. See Omnibus Budget Reconciliation Act of 1986, Pub. L. No. 99-509, § 6002(a)-(c), 100 Stat. 1874, 1931-33 (codified at 5 U.S.C. § 8348(j)-(l)) (the "1986 Amendments").

Under the 1986 amendments, "the Secretary . . . may suspend additional investment of amounts in the Fund if such additional investment could not be made without causing the public debt of the United States to exceed the . . . debt limit." 5 U.S.C. § 8348(j)(1). The 1986 amendments also provide that "the Secretary . . . may sell or redeem securities, obligations, or other invested assets of the Fund before maturity in order to prevent the public debt of the United States from exceeding the . . . debt limit." Id. § 8348(k)(1). The Secretary's redemption authority may be exercised, however, "only during a debt issuance suspension period, and only to the extent necessary to obtain any amount of funds not exceeding the amount equal to the total amount of the payments authorized to be made from the Fund" during the debt issuance suspension period. Id. § 8348(k)(2)

http://www.justice.gov/olc/civser11_rev.htm