Just by being accused by IRS of owing $50K or more in back taxes a person can be prevented from traveling abroad. It is totally unconstitutional conflicting with USA Constitution forbidding "Bills of Attainder" including bills of "pains and penalties".See following and link to article :
U.S. Constitution: Article I
Clause 3. No Bill of Attainder or ex post facto Law shall be passed .
''Bills of attainder . . . are such special acts of the legislature, as inflict capital punishments upon persons supposed to be guilty of high offences, such as treason and felony, without any conviction in the ordinary course of judicial proceedings. If an act inflicts a milder degree of punishment than death, it is called a bill of pains and penalties. . . . In such cases, the legislature assumes judicial magistracy, pronouncing upon the guilt of the party without any of the common forms and guards of trial, and satisfying itself with proofs, when such proofs are within its reach, whether they are conformable to the rules of evidence, or not. In short, in all such cases, the legislature exercises the highest power of sovereignty, and what may be properly deemed an irresponsible despotic discretion, being governed solely by it deems political necessity or expediency, and too often under the influence of unreasonable fears, or unfounded suspicions.'' 1701 The phrase ''bill of attainder,'' as used in this clause and in clause 1 of Sec. 10, applies to bills of pains and penalties as well as to the traditional bills of attainder. 1702
link: http://caselaw.lp.findlaw.com/data/constitution/article01/47.html
It is said that this tyrannical legislation will be passed by a Republican controlled House. It is true that the so called reps in the House never, ever defer to the USA Constitution before they vote on legislation. And even if they did consider the USA Constitution this reprobate group would ignore it as is said to be the case in this situation. Which is why Washington DC is satirically referred to as "Washington District of Criminals".
PS: California Senator Barbara Boxer is said to be the person who initially introduced the part of the bill containing the "bill of Attainders" or "bill of pains and penalties".
see link: http://www.infowars.com/bill-allowing-irs-to-revoke-passports-described-as-stalinist/