Since when do machetunim of Vice-Presidential candidates get Secret Service protection??

Why was Sherry Johnston, Sarah Palin's supposed future mother-in-law, under Secret Service protection during the election campaign?

The mother of Bristol Palin's boyfriend sent text messages discussing drug transactions less than a month after the young woman's mother, Alaska Gov. Sarah Palin, was nominated as the Republican vice presidential candidate, according to court documents filed this week.

[snip]

Authorities say the case against Sherry Johnston began in the second week of September, when drug investigators intercepted a package containing 179 OxyContin pills. That led to the arrest of the suspects, who agreed to be informants.

According to the affidavit, Johnston sent a text message to one informant Oct. 1, writing: "Hey, my phones are tapped and reporters and god knows who else is always following me and the family so no privacy. I will let u no when I can go for cof."

The trooper's affidavit indicates that Sarah Palin's candidacy factored into the investigation, with state officials delaying execution of a search warrant until this month, when Johnston was "no longer under the protection or surveillance of the Secret Service."

It is not normal procedure for people beyond a candidate's immediate family to receive Secret Service protection. Here's who the Secret Service is authorized to protect:

* The president, the vice president, (or other individuals next in order of succession to the Office of the President), the president-elect and vice president-elect
* The immediate families of the above individuals
* Former presidents and their spouses for their lifetimes, except when the spouse remarries. In 1997, Congressional legislation became effective limiting Secret Service protection to former presidents for a period of not more than 10 years from the date the former president leaves office
* Children of former presidents until age 16
* Visiting heads of foreign states or governments and their spouses traveling with them, other distinguished foreign visitors to the United States, and official representatives of the United States performing special missions abroad
* Major presidential and vice presidential candidates, and their spouses within 120 days of a general presidential election
* Other individuals as designated per Executive Order of the President
* National Special Security Events, when designated as such by the Secretary of the Department of Homeland Security

It says nothing there about "the mother of your daughter's boyfriend." So why was Sherry Johnson under the protection and/or surveillance of the Secret Service? Did George W. Bush authorize her to receive this protection? And why would this unusual Secret Service protection prevent issuing of a warrant if the Alaska state troopers had reason to believe a crime was being committed?