Former Mayor Bob Filner’s legal problems appear to be multiplying. Aside from a civil sexual harassment suit, county grand jury proceedings that could lead to criminal charges are now in play. The grand jury’s investigation was first brought to light by U-T San Diego, which anonymously quoted two attorneys as saying their clients will soon testify in what figures to be the context of sexual harassment allegations. State attorney general’s deputies will handle the secret Q&A – with Filner’s lawyer barred from attending. Local defense attorneys not involved in the case say grand jury probes give prosecutors a home-field advantage, as opposed to filing criminal complaints and taking defendants to preliminary hearings. “A grand jury, because they’re with a particular prosecutor for a long period of time, kind of attaches themselves to them,” says Marc Carlos, a veteran defender of grand jury targets.